在本論文中，我們更細微的研究摻雜染料之聚合物混合液晶(DDPDLC)光柵形成的動態過程，使用Q開關Nd:YAG 雷射，其輸出為約8ns脈衝(λ=532nm)，兩道相干的線性偏振激發光束，以一個脈衝照射在DDPDLC的材料上，用s及p線性偏振He-Ne雷射光同時偵測一階繞射強度之動態變化：更證實偶氮染料分子（Methy1 Red）在干涉條紋光強處受光激發之後，會先轉至垂直於光場偏振方向，再擴散及吸附到液晶顆粒的內面，形成永久的表面錨定力，對液晶提供垂直激發光場方向的負向力矩。因此在光強處的液晶會被轉動到垂直光場的方向而不同於光弱處(仍維持在random的狀態)，而形成全像的光柵；再者，光學儲存除了強調寫入的時間短外，更要要求其記錄達穩態的時間及強度，所以我們藉由改變激發光的強度、MR濃度及LC 液晶顆粒的大小，來最佳化穩態記錄的時間及繞射強度。最後我們用鎖模Nd:YAG雷射（duration~30ps） 一個脈衝照射下，發現具有更快速記憶的效果，將快速記憶又推向更高的成次。

In this thesis, we study the dynamic behavior of the holographic grating written in Dye-Doped Polymer-Dispersed Liquid Crystal (DDPDLC) films. The grating is written by using a Q-switched second-harmonic generation Nd:YAG pulse(λ=532nm, duration~8 ns), while probed by a He-Ne laser. From the dynamic study of the first order diffraction intensity of the probe beam, we believe that the photoexcited dye molecules are diffusing and adsorbing onto the wall of droplets and inducing a negative reorientational torque to align the liquid crystal molecules within a droplet in the high-intensity regions of the interference patterns. Thus the orientation of LC molecules in high-intensity regions of interference pattern differs from that in low-intensity regions, resulting in the formation of a holographic grating. For optical storage, we emphasize not only a short recording time but also a short stabilization time and a high stabilization intensity. In order to find the optimum conditions (i.e., short stabilization time and high stabilization intensity), several parameters, such as the pump beam intensity, Methyl Red concentration and LC droplet size were varied to study the characteristics of the formed grating. Finally, we performed a fast optical recording based on DDPDLC films using a mode-locking second-harmonic generation Nd:YAG pulse (duration~30ps).

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